projid - the project name mapping file
The /etc/projid file provides a mapping between numeric project
identifiers and a simple human readable name (similar relationship to
the one that exists between usernames and uids). Its format is simply:
# comments are hash-prefixed
# ...
cage:10
logfiles:42
This file is optional, if a project identifier cannot be mapped to a
name, it will be parsed and displayed as a numeric value.
xfs_quota(8), xfsctl(3), projects(5).
projid(5)